High-temperature abrasion-resistant coating on a ferrous metal substrate

Abstract

A method of forming a high-temperature abrasion-resistant hard facing or coating on a ferrous metal substrate by employing an aluminothermic reduction reaction. The resultant article has a hard facing layer containing from 2 to 8 percent boron. Hard faced composite articles made by the invented method, such as sintering machine crash decks, coke pusher ram shoes and grizzly bars are also disclosed.

We claim: 
     
       1. A coke pusher ram shoe comprising a multiplicity of abrasion-resistant metal composites, each composite comprising a metal substrate and a metallurgically bonded hard facing layer consisting essentially of an iron matrix containing from about 45 to about 80 volume percent Fe 2  B, said composites fixed together in such manner that the hard facing layer of each forms the wearing surface of said shoe. 
     
     
       2. An abrasion-resistant composite coke pusher ram shoe comprising a metal substrate having beveled edges and a hard facing layer consisting essentially of an iron matrix containing from about 45 to about 80 volume percent Fe 2  B metallurgically bonded to each beveled edge and to the short face of said substrate between said beveled edges. 
     
     
       3. A chute for transferring granular material comprising at least two elongated metal components fastened together in an elongated relationship, each metal component having a hard facing ferrous metal layer thereover having a thickness greater than 0.1 inch metallurgically bonded thereto by an aluminothermic reduction reaction, said hard facing layer consisting essentially of iron and from 4 to 7 percent boron, to yield a ferrous metal matrix containing from 45 to 80 volume percent Fe 2  B.